Rick,
Just planting seeds from my years of battling with stupid graffiti NOT artist. Aint got time for helping remove the stupids at D.C. booo whoo....
That MEK stuff should only be used by the professionals. I used it once to clean out my gas tank on an old car. Nobodies lungs are strong enough for that smoky stuff. I saw some Kutzit last year somewhere, I am sure it is better for the environment than MEK. All paint removers have trace amounts of MEK in them as an active ingredient. I estimate that only one gallon would do the job there. At least it would put a big dent in the removal of that eye sore and one could figure how much more to bring later.
Good luck and happy hot potin'.
Enjoy your new clear bottom big pool at D.C.H.S. !